Gear quadrant and selector bushes - sizing

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As well as sorting the engine I thought I'd take a look at reasons for difficult gear selection (only neutral to 1st when hot). This has got to be annoying in traffic and have to pull away in 2nd. What I found is selectors and gears sliding nicely, no restrictions in the change mechanism and pawl is OK but I do have a knackered 1st gear bush. Now I've had it subjectively worse so I don't think its the whole reason. However, the quad and selector bushes appear on the limit but difficult to measure the bore accurately. I have measured the shafts with a mic and they come in at 0.4978" and bushes over 0.500". There is a lot of rock and the quadrant has been scraping on the housing, presumably wear or bushes not in far enough?

A couple of questions.....
I bought new bushes many years ago but never fitted them. Anyway I found and fitted them and they need reaming as expected. Do the experts feel this is possible with an adjustable reamer (I've heard they are only good for cleaning up holes) or should it be a fixed size tool?

I cannot find any dimension to press to. Before removal they protruded by 0.040" and 0.050" into the shell. Is this acceptable or should they sit flush with the bore externally? I can see nothing on Old Britts inspect/rebuild guides nor even an old Mick H article from ’87. Nothing in the Norton workshop manual either, just the clearance specs.

I’ve had these boxes apart many times so I’m pretty familiar with them but never done these bushes……….appreciate any input gents. Thanks.
 
they should be flush fit to the outside in the counter bore and protrude inside.

Keith1069 said:
I cannot find any dimension to press to. Before removal they protruded by 0.040" and 0.050" into the shell. Is this acceptable or should they sit flush with the bore externally? I can see nothing on Old Britts inspect/rebuild guides nor even an old Mick H article from ’87. Nothing in the Norton workshop manual either, just the clearance specs.
 
Thanks Bill. I just remembered an old Dommie casing bought as a spare and found that to compare. Cheers.
 
bill said:
they should be flush fit to the outside in the counter bore and protrude inside.

Keith1069 said:
I cannot find any dimension to press to. Before removal they protruded by 0.040" and 0.050" into the shell. Is this acceptable or should they sit flush with the bore externally? I can see nothing on Old Britts inspect/rebuild guides nor even an old Mick H article from ’87. Nothing in the Norton workshop manual either, just the clearance specs.

The bushes should fitted by heating the case and should fit so their is room for the O rings inside the casing so the washer just slightly compresses to Oring against the bush to prevent oil loss
 
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